Want and Can · -고 싶어요, -(으)ㄹ 수 있어요

4. Common mistakes

❌ Mistake 1 — 싶어해요 for yourself

✖ 저는 가고 싶어해요.
✔ 저는 가고 싶어요.
  jeo-neun ga-go si-peo-yo.

싶어해요 is for other people, so it is not right when you say what you want yourself. The sentence is grammatical, but it sounds like you are describing someone else. Use 싶어요 for "I".

❌ Mistake 2 — Only ㄹ after a consonant stem

✖ 먹ㄹ 수 있어요.
✔ 먹을 수 있어요.
  meo-geul su i-sseo-yo.

먹다 has a consonant stem, so it needs the full syllable 을. You cannot put ㄹ after a consonant, because the stem already has a final sound. The same rule is true for 읽다, so say 읽을 수 있어요.

❌ Mistake 3 — Adding 을 to a ㄹ-stem

✖ 만들을 수 있어요.
✔ 만들 수 있어요.
  man-deul su i-sseo-yo.

만들다 already ends in ㄹ, so no extra 을 is needed. Just add a space and 수 있어요. This is the same for 살다, which gives 살 수 있어요.

❌ Mistake 4 — No space before 수

✖ 갈수 있어요.
✔ 갈 수 있어요.
  gal su i-sseo-yo.

수 is its own word, so it needs a space on both sides: 갈 수 있어요. Writing it joined to the verb is a spelling error. Remember that the pattern is three words.

❌ Mistake 5 — 싶어요 for something in the past

✖ 어제 영화를 보고 싶어요.
✔ 어제 영화를 보고 싶었어요.
  eo-je yeong-hwa-reul bo-go si-peo-sseo-yo.

The sentence with 싶어요 is grammatical, but it does not fit 어제 (yesterday). It means you want to see a movie now. To say you wanted to, change the ending to 싶었어요, so this is wrong for the meaning "wanted".